Both ends of the channel are sealed, a needle and gauge are inserted, and the channel is pressurized to 25 to 35 psi, higher for thicker sheet, then held for 5 minutes. A drop beyond the allowed limit means a leak somewhere along the seam. The far end is then cut open to prove air reached the whole length, because a blocked channel can hold pressure falsely.
Air channel test held 30 psi for five minutes, now cut the far end and make sure the gauge drops.
A channel pinched shut partway along holds pressure on only part of the seam, so a test without the far-end release proves nothing.
Also heard as
- air pressure test
- air test
- channel test
- pressure test
Related terms
Fusion weld
Geomembrane seam made by melting the facing surfaces of two overlapped sheets and pressing them together.
Vacuum box
Clear-topped box pulled to a vacuum over soapy geomembrane so leaks in seams and patches show up as bubbles.
CQA
Construction quality assurance: independent monitoring and testing that a geosynthetic system was built as designed.
Destructive test
Testing seam samples cut from installed geomembrane in peel and shear to prove seam strength.